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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:36.0pt">
I'm aware of substTys being currently unchecked, I didn't want to introduce substTysUnchecked just yet, as there already are more than 30 occurrences of substTyUnchecked. But maybe I should push uncheckedness as far up as possible, do you think it's worth to
do it now? <o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Well, it’s just as much a source of potential bugs as substTy. So yes, I’d make all the calls to substTysUnchecked, and then work through getting rid of them. Many
of them will be simple.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:36.0pt">
Do you want me to do the renaming?<o:p></o:p></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">yes please<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">Pls yell specifically when you need help; don’t rely on me seeing Phab patches<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US">S<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Calibri",sans-serif;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span lang="EN-US" style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Bartosz Nitka [mailto:niteria@gmail.com]
<br>
<b>Sent:</b> 26 January 2016 11:15<br>
<b>To:</b> Simon Peyton Jones <simonpj@microsoft.com><br>
<b>Cc:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> Re: Substitutions<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
Hello Simon,<o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
I was about to send an improved version of D1801, I will do that once I rebase past your patch (there's a small overlap with what I've done). D1820 is ready for review.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
I have a patch coming for piResultTys [1] where the FVs of ty are not in the in_scope set. I've also looked at a similar problem in lint_app [2], but the fix I have is a bit awkward, so I will probably need some input from you. Both of them are blocking #11360
and I want to get it unblocked as soon as possible to continue determinism work.<o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
I'm aware of substTys being currently unchecked, I didn't want to introduce substTysUnchecked just yet, as there already are more than 30 occurrences of substTyUnchecked. But maybe I should push uncheckedness as far up as possible, do you think it's worth to
do it now? <o:p></o:p></p>
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<o:p> </o:p></p>
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Do you want me to do the renaming?<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
<o:p></o:p></p>
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Cheers,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
Bartosz<o:p></o:p></p>
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<o:p> </o:p></p>
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[1] <a href="https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/types/Type.hs;016a0bd1ba129134dfa612db0d96e01644fa7b9f$803-804">https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/types/Type.hs;016a0bd1ba129134dfa612db0d96e01644fa7b9f$803-804</a><o:p></o:p></p>
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[2] <a href="https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/coreSyn/CoreLint.hs;016a0bd1ba129134dfa612db0d96e01644fa7b9f$1134">https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/coreSyn/CoreLint.hs;016a0bd1ba129134dfa612db0d96e01644fa7b9f$1134</a><o:p></o:p></p>
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<o:p> </o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:6.0pt;margin-right:0cm;margin-bottom:6.0pt;margin-left:0cm">
2016-01-26 10:55 GMT+00:00 Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com" target="_blank">simonpj@microsoft.com</a>>:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Bartosz<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">How are you getting on with tidying up substitutions.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I’ve done a bit in that direction myself:<o:p></o:p></p>
<p style="margin-left:36.0pt">commit 1c6d70c2121fd1126fcc2458bdbcc856e19598c2<o:p></o:p></p>
<p style="margin-left:36.0pt">Author: Simon Peyton Jones <<a href="mailto:simonpj@microsoft.com" target="_blank">simonpj@microsoft.com</a>><o:p></o:p></p>
<p style="margin-left:36.0pt">Date: Tue Jan 26 09:37:06 2016 +0000<o:p></o:p></p>
<p style="margin-left:36.0pt"> <o:p></o:p></p>
<p style="margin-left:36.0pt"> Kill off zipTopTCvSubst in favour of zipOpenTCvSubst<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">But there is more to do.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">In particular, I note that
<b>substTys is not checked</b> – but neither is it called substTysUnchecked. It should be! That will show up a bunch more cases, I think.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Another particular thing, arising from my patch, is that
<b>we can now do some renaming</b><o:p></o:p></p>
<p><span style="font-family:Symbol">·</span><span style="font-size:7.0pt">
</span>zipOpenTCvSubst -> zipTvSubst (It only deals with tyvars)<o:p></o:p></p>
<p><span style="font-family:Symbol">·</span><span style="font-size:7.0pt">
</span>zipOpenTCvSubstCoVars -> zipCvSubst (it only deals with covars)<o:p></o:p></p>
<p><span style="font-family:Symbol">·</span><span style="font-size:7.0pt">
</span>zipOpenTCvSubstBinders -> zipTyBinderSubst (it only deals with TyBinders, not covars)<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I guess you’ll want to do similar things for the “mk” variants.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Anyway: good for you! Let me know if you need help.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="color:#888888">Simon<o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="color:#888888"> <o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="color:#888888"> <o:p></o:p></span></p>
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